Optical semiconductor device with diffraction grating structure
US5926493A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 20, 1997 |
| Grant date | Jul 20, 1999 |
| Priority date | — |
| Expiry date | May 20, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01S5/3432
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Optical semiconductor devices with integrated diffraction gratings with higher quality are realized through the use of Al-free grating layers. AlGaAs/GaAs regime optical semiconductor devices, such as laser diodes or optical filters, conventionally utilize an AlGaAs grating layer that has a strong affinity for oxidation. Instead of a Al-containing layer, a quantenary, InGaAsP grating layer is utilized, lattice matched to the underlying AlGaAs/GaAs structure, substantially eliminating any problem of oxide contamination. Also, an Al-free, ternary InGaP grating layer is utilized in the InGaP/InGaAsP/GaAs material regime. The quantum well active region of these devices may also be modified to extend the gain bandwidth of operation of these devices to insure continued operation over a wider temperature range with the wavelength peak of the grating in that the wavelength peak of the grating more assuredly remains within the wavelength operating range of the device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.